In the packaging industry, manufacturing folding boxes is carried out traditionally on lines, by folding and gluing blanks by means of machines, commonly called folder-gluer machines. In this regard, it is known to inspect the quality of blanks within the same folder-gluer. For this, a specific module is used and is directly integrated into the folder-gluer. This module is able to individually inspect each blank when it passes through the module. As the moving of blanks is done on the printed face turned towards the back within the folder-gluer, their transportation through the inspection module is carried out by holding them by the top, while they are inspected on the bottom.
In practice, transporting the blanks by their tops is done by using a vacuum conveyor unit, which connects multiple conveying belts to a vacuum box positioned directly above. Each blank is thus held by the top of its internal face, so that its printed face, which is turned towards the bottom, is entirely clear. Inspecting its bottom is carried out by a camera, which is set up under the vacuum conveyor unit, and which functions at a low angle. The camera is connected to a suitable lighting system. The camera takes a photo of each printed face, progressively as the blanks scroll through.